Abstract. Modern distributed applications are typically obtained by integrating new code with legacy (and possibly untrusted) third-party services. Some recent works have proposed to discipline the interaction among these services through behavioural contracts. The idea is a dynamic discovery and composition of services, where only those with compliant contracts can interact, and their execution is monitored to detect and sanction contract breaches.

In this setting, a service is said honest if it always respects the contracts it advertises. Being honest is crucial, because it guarantees a service not to be sanctioned; further, compositions of honest services are deadlock-free. However, developing honest programs is not an easy task, because contracts must be respected even in the presence of failures (whether accidental or malicious) of the context.

In this paper we present Diogenes, a suite of tools which supports programmers in writing honest Java programs. Through an Eclipse plugin, programmers can write a specification of the service, verify its honesty, and translate it into a skeletal Java program. Then, they can refine this skeleton into proper Java code, and use the tool to verify that its honesty has not been compromised by the refinement.